Years after the mission, Jim Lovell acknowledged that they figured the odds of making it out of earth's orbit, around the moon multiple times, and back to earth safely were 50-50 or less. Sounds optimistic to me.

Bill Anders took this incredible photo on December 24, 1968. The image became the inspiration for the first Earth Day in 1970. This is what the US government might classify as an "unintended consequence" of the space program.

UDT clad divers meeting the capsule.

The Apollo 8 capsule on the deck of the USS Lexington.

This is the after-mission party for Apollo 8...they knew how to rage back then!